1. Field of the Invention
The subject invention relates generally to float operated level indicator devices and, more particularly, to a concrete level indicator float device for indicating the level of concrete being filled in the hopper of a concrete pump in order to prevent accidental overflow and spillage.
2. Discussion of the Related Art
In the construction industry, concrete mixer trucks are used to mix and deliver tons of concrete to all types of projects at commercial and residential construction sites. The well known concrete mixer truck includes a cab for the operator to drive the vehicle, an air supply, a mixing drum, frames to support the mixing drum, a charge hopper, a discharge hopper, an extendable delivery chute and controls for operating the mixing drum and hoppers. Most mixer trucks are provided with a first set of controls inside the cab and a second set of controls at the rear of the vehicle, near the discharge hopper. Either set of controls can be used to operate the discharge hopper in order to selectively start and interrupt the discharge of concrete therefrom. Normally, the delivery chute is attached to the discharge hopper for directing the flow of discharged concrete to a desired location. In many instances, however, the site where the concrete is needed for construction is not within reach of the mixer truck and delivery chute. In this situation, which is typical at many construction sites, a concrete pump is used for moving the loose concrete mixture from the mixer truck discharge site to a pour site where a concrete structure is being formed, such as a deck, floor slab, support column, or wall.
A typical concrete pump used at many construction sites includes a hopper for receiving the loose concrete mixture which is discharged from the mixer truck. Concrete pumps are commonly mounted on a trailer and have hoppers ranging in holding capacity of between 8-12 cubic feet. The hopper is open at the top and may be fitted with one or two screens for separating rocks and other large chunks of material from the concrete mixture as the concrete mixture is being filled through the open top of the hopper. The separator screens in the hopper resemble a grill and have parallel bars which are spaced apart to define a screen size such that objects larger than the spacing between the bars are prevented from passing through the screen. Depending upon the type of concrete structure being formed and the size of the hose being used to transport the concrete, either one or two screens of different size may be used.
In many instances, the operator of the mixer truck may choose to remain in the airconditioned or heated cab while operating the controls which discharge the concrete from the mixing drum of the truck and into the hopper of the concrete pump. And, while this manner of operation is often preferable to the truck operator, it can be particularly troublesome to the concrete pump operator. Because the demand for concrete being moved by the concrete pump is rarely the same as the rate of concrete discharge being filled in the hopper, it is usually necessary to frequently interrupt concrete discharge from the mixing truck until the level in the pump hopper is lowered. When in the cab, the mixer truck operator is unable to see the level of concrete in the pump hopper and relies on signals from the pump operator to start and interrupt discharge. On occasion, the mixer truck operator may fail to react to the signals of the pump operator when the pump hopper is full and the discharge of concrete from the mixer truck continues to flow. Eventually, the concrete mixture will overflow the pump hopper and spill down the outer sides of the concrete pump apparatus and onto the ground. Accidental spills of this nature subject the pump operator to a time consuming and costly cleanup process and may result in damage to the concrete pump apparatus and trailer.
Accordingly, there remains an urgent need in the construction industry, and particularly in the field of concrete construction, for a device which indicates the level of concrete in the hopper of a concrete pump. More particularly, there is a need for a concrete level indicator device which will help to avoid accidental overflow and spillage of concrete being filled in the hopper of a concrete pump.
With the foregoing in mind, it is primary object of the present invention to provide a concrete level indicator for use on concrete pumps to indicate the level of concrete being filled within the hopper of the pump, and thereby preventing accidental overflow and spillage of concrete.
It is a further object of the present invention to provide a concrete level indicator device which helps to avoid overflow and spillage of concrete being filled in the hopper of a concrete pump, thereby preventing time consuming and costly cleanup of the concrete pump, as well as preventing potential damage to the concrete pump.
It is still a further object of the present invention to provide a concrete level indicator for indicating the level of concrete being filled in the hopper of a concrete pump, and wherein the device is structured to have an entirely mechanical operation with few moving parts.
It is still a further object of the present invention to provide a concrete level indicator for indicating the level of concrete being filled in the hopper of a concrete pump, and wherein the device is constructed of durable, non-corrosive materials.
It is still a further object of the present invention to provide a concrete level indicator for indicating the level of concrete being filled in the hopper of a concrete pump, and wherein the device is easy to clean after each use.
It is still a further object of the present invention to provide a highly durable, low maintenance concrete level indicator device for use on concrete pumps, and wherein the device is easy to assemble, install and operate.
It is yet a further object of the present invention to provide a concrete level indicator device having all of the advantages as set forth above, and wherein the device is relatively easy to manufacture, of low cost and affordable to all of those having a need for the device.
These and other objects and advantages of the present invention are more readily apparent with reference to the detailed description of the invention and accompanying drawings.
The present invention is directed to a device for indicating the level of concrete within the hopper of a concrete pump and includes an elongate post with an enlarged float fixed to the bottom end. The float sits on the top of the concrete in the hopper and a guide sleeve surrounding the post allows vertical telescoping movement of the post as the level of concrete changes. A retaining collar attaches to a screen in the hopper of the pump and surrounds the guide sleeve. The retaining collar limits swinging movement of the post and guide sleeve, thereby maintaining the device in a vertical position within the hopper. As concrete is filled into the hopper, the post rises through the guide sleeve until a visual indicator (e.g. a red band) on the top end of the post is visibly exposed above the guide sleeve, thereby alerting the operator to stop the discharge of concrete being filled in the hopper until the concrete level drops and the visible indicator on the post is no longer visible.
For a fuller understanding of the nature of the present invention, reference should be made to the following detailed description taken in conjunction with the accompanying drawings in which:
FIG. 1 is a perspective view showing a typical trailer-mounted concrete pump and concrete mixer truck positioned for discharging a loose concrete mixture into the hopper of the concrete pump while the operator of the truck is seated in the cab and viewing the discharge operation and pump hopper through a side view mirror, and wherein the operator""s line of sight is indicated in broken lines;
FIG. 2 is isolated top perspective view illustrating the concrete level indicator device of the present invention installed within the hopper of a concrete pump in accordance with a first preferred embodiment thereof, wherein two separator screens are used in the hopper;
FIG. 3A is a side elevational view, in partial section, showing the concrete level indicator device of FIG. 2 installed in the hopper of a concrete pump, and wherein a visual indicator of the device is in a raised position to indicate that the concrete level in the hopper has reached full;
FIG. 3B is a side elevational view, in partial section, showing the concrete level indicator device of FIG. 2 installed in the hopper of a concrete pump, and wherein the visual indicator of the device is lowered and concealed from view to indicate a low concrete level within the hopper;
FIG. 4 is an exploded perspective view showing the component parts of the concrete level indicator, in accordance with a second preferred embodiment thereof; and
FIG. 5 is an isolated top perspective view showing the concrete level indicator of the second preferred embodiment installed within the hopper of a concrete pump, and wherein only a single separator screen is used within the hopper.